Benchmark: getElementsByClass vs. querySelector

HTML Preparation code:

<div class="wrapper">
  <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
    <div class="item"></div>
</div>
<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js'></script>

Tests:

queryselector
document.querySelector(".item");
class by name
document.getElementsByClassName("test");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
queryselector
class by name

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.212 Safari/537.36

Browser/OS: Chrome 90 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
queryselector	4989222.0 Ops/sec
class by name	4411250.0 Ops/sec

getElementsByClass vs. querySelector (version: 0)

Comparing performance of: queryselector vs class by name

Created: 4 years ago by: Guest

Jump to the latest result

queryselector

class by name

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A